Food web structure and resilience to nutrient inputs
The structure of a food web, specifically the strength and number of interactions, influence the ecosystem’s response to perturbations. Leveraging a large-scale commercial fish harvesting effort in shallow lakes, we are investigating the role of changing food web structure in resilience to nutrient pulses from large storm events. In addition to monitoring changes in the food webs of harvested lakes (Wilkinson et al., in review), we are using experimental ecosystems, historical community data from restored lakes, and food web models to understand how food web structure mediates the link between nutrient loading and blooms. This work is being led by Tyler Butts and funded through the Iowa Department of Natural Resources, North Temperate Lakes LTER, and the National Science Foundation.
Consumer-driven nutrient recycling
We are investigating functional trait diversity and eco-evolutionary dynamics in zooplankton and the consequences this variation has on ecosystem functioning. We have found that the functional trait composition of zooplankton communities shifts with eutrophication, as more nitrogen-rich taxa dominate in the most eutrophic lakes (Moody & Wilkinson 2019). This has consequences for phosphorus availability, particularly in the spring and early summer, in hypereutrophic waters (Butts et al. in review).
Daphnia are thought to face a trade-off between P-limited growth in low-nutrient lakes and the costs of excreting excess phosphorus in high-nutrient lakes. Led by Dr. Eric Moody, we investigated trait variation in Daphnia using common garden experiments to understand how local adaptation may allow this keystone grazer to persist in phosphorus-rich lakes (Moody et al. 2021). This work was funded by the USDA NIFA.